Such ambiguities will recall Cold War paranoia for those who tasted it, as will details such as the circular mouths of wailing children, reduced to silent blots of flat color.

Hoff's art depends on a balance of humor and inside-out nostalgia. He loses that balance in several recent "flowers" that have a Koons-like archness about them.

But Hoff's more effective pieces, including some of the simplest, sensitize us to the whiff of betrayal, of damaging dishonesty, in all forms of sentimentality.

Hoff shares space at Schwartz with Gwen Manfrin, whose photo-based gouache and charcoal drawings assay the demeanor of female adolescents. Viewers must bring to the drawings their own curiosity about Manfrin's theme. Her images will not stir it.

"Marking" at Arts Commission: "Marking Time Mapping Thought" at the San Francisco Arts Commission Gallery gathers work by five contemporary artists who let systems determine the final form of what they make.

The drawing on view looks like an abstraction. Each rectangle in its grid represents a batter and contains marks that notate his performance. How much difference does it make whether or not we can read the symbolism of Walton's notation? In terms of visual pleasure, probably very little. But as to appreciating his generative idea, the ability to read what we see might matter a lot.

A similar tangency between two modes of appreciation figures in other works on view. Nigel Poor inscribed small clayboard panels with words and phrases that caught her ear as she listened to the radio during long hours alone in the studio. Each time she ran into an edge while printing a line, she would rotate the panel and continue writing in another direction. The ricochet of lines within the small space of each panel and the fineness of her inscriptions makes the panels nearly unreadable except as graphic performances.

The paintings of Chicagoan Michael Banicki initially resemble those of Teo Gonzalez: fine grids filled with droplets of color. But each color dot in Banicki's work represents a degree of preference, each cell of a grid marks a comparison between two specific things, such as rivers in Wisconsin or jazz trumpeters. Each dotted field as a whole plots the pattern of the artist's comparative preference, a shimmer of useless -- to us -- information about him. Perhaps people who have no understanding of abstract painting perceive it in just those terms. But Banicki disarmingly satirizes the idea of the visual artist as an athlete of sensibility.

Los Angeles artist Bari Ziperstein gets a room to herself at the SFAC in her first San Francisco outing.

Ziperstein can claim a context for what she does in work by such artists as Joseph Beuys, Imi Knoebel, Jason Rhoades and Jessica Stockholder that blurs the line between display and storage.

For her centerpiece, Ziperstein has built a loose floor-to-ceiling monolith of cardboard boxes. She has coated many of their inward-facing surfaces with neon-bright color. Its reflected glow seeps from the structure's interior.

With "10 x 10: 8 Week Lease (Reluctant Monument)" (2005), as she calls it, Ziperstein has cut a new middle path between the geometry and blankness of minimalism and the consumer culture reference of Pop art. (Think of Andy Warhol's seminal "Brillo Boxes.")

Imagine Ziperstein's work without that background and you begin to see it as a thin accomplishment.

Darling at 16: Northern Californian Lowell Darling has a better eye than most conceptual artists, as his show at Gallery 16 makes apparent.

This exhibition features photo collages and notebook pages turned out as sufficient artworks -- involving in every degree, including the least.

But at its heart hang half a dozen long scrolls that reproduce immensely magnified bits of film footage found by Darling during years of Hollywood scavenging.

In "Untitled #5 (Hollywood Archaeology)," frames from an instructional film about telling time repeat the question "What time is it?" beneath a clock face given an apocalyptic complexion by the damage the film has undergone.

Darling's "Hollywood Archaeology" series can make us wonder whether a lifetime of watching film narrative has not made fatalists of us all, whatever our consciously held beliefs.